Electrically controlled hoist for monorails



1944. A. L. MEDENWALD ET AL ELECTRICALLY CONTROLLED HOIST FOR MONORAI ELS Filed Sept. 22, 1941 3 Sheets-Sheet 1 3g JINVEQTORS (Fa 2Z6. Am

' Oct. 17, 1944. A. 1.. MEDENWALD ET AL 2,360,505

7 ELECTRICALLY CONTROLLED HOIST FOR MONORAILS Filed Sept. 22, 1941 s Shee ts-Shee 2 MT. R 3 N u l k &H 8 3 8 3 m 3. [I u 8 o \w .2 N M b. 3 MM & Q Q a. mm mm Q a v R. Q ,r Q 2 m an Q Q 13 RN mm 2 \v INVENTORS,

Oct. 17, I944.

ELECTRIGALLY CONTROLLED HOIST FOR MONORAILS A. MEDENWALD ETAL' Filed Sept. 22,.

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1941 :5 Sheets-Sheet a III ////A Patented Oct. 17, 1944 ELECTRICALLY CONTROLLED HOIST FOR MONORAILS Arthur L. Medenwald, Los Angeles, and Earl B. Spencer, Pasadena, Oalifl, assignors to Earl B. Spencer and George B. Morris, copartners, doing business as Spencer & Morris, Los Angeles,

Calif.

Application September 22, 1941, Serial No. 411,838

1 Claim.

Our invention relates to electrically controlled hoists for monorails such as are moved on overhead track or rails and which, in their course of travel, make a loop, or are turned around on a turntable, and returned to the track or rail on which they first approached the loop or turntable, thus reversing the position of the hoist on the track.

It is a well known fact that in a three phase alternating current system where three conductors are used, the crossing of any two conductors affects a reversal in the direction of the rotation of the motor, and it will be seen that in a group of tracks where switches or turntables are interposed, or where there is a loop in the circuit coming back into the main line, there would be a reversal of the motor, which would not only upset the marking of the forward and reverse or up and down switches, but what is still more hazardous is that it would make ineffective the usual protective devices, such as the limit switch or stop.

In order to overcome this difficulty, we have devised a system in which we interpose an auxiliary, phase reversing switch which affects the phase of the current so as to offset any reversal caused by turning the hoist around in the course of its travel, as by making a loop.

This auxiliary switch is mechanically actuated by collector or trolley wheels running on a trolley bar which is in a different position relative to the other or regular trolley bars of the system. When these trolley bars are inthe regular or uniform positions or elevations, the current is undisturbed, but if the hoist is turned around and the trolley bar on the opposite side is lower, as we propose, then when the collector or trolley wheel passes under it, the forcing of said collector trolley wheel down by said lower trolley bar automatically actuates said auxiliary reversing switch, which operates to reverse the motor also.' This takes place just as the traveling hoist reaches the particular point where the trolley wheels or collectors move upon the lower trolley bar and cause the actuation of the reversing switch.

In order to explain our invention, we have shown on the accompanying three sheets of drawings one practical embodiment thereof, which we will now describe:

Figure 1 is a plan view of a system of tracks to be traversed by a traveling hoist, with a plurality of turn table switches for changing the course of the traveling hoist;

Figure 2 is a fragmentary view showing a turn table adjusted for straight track travel through the turn table;

Figure 3 is a wiring diagram used in controlling the operation of the traveling hoist;

Figure 4 is a portion of the wiring diagram showing the changed position of the controlling or reversing switch;

Figure 5 is an enlarged plan view of one of the turntable switches, with parts broken out for explanatory purposes;

Figure 6 is an enlarged sectional view taken on line $6 of Fig. 5, showing the motor operated hoist;

Figure 7 is a similar View taken on line l--'I of Fig. 5;

Figure 8 is an enlarged View of one of the supports for the trolley members of the system, and on which the trolleywheels of the hoist mechanism run; and

Figure 9 is a vertical sectional view taken on the line 9-9 of Fig. 8.

Referring now in detail to the drawings, overhead supporting I-beams H! are shown as track ways or members, said I-beams or members being connected at places with channel members, H, and shown as welded endwise against the sides of said I-beams 10.

The turntable switch members are formed. of channel members l2, l2, and are provided on their outer sides with wheels, l3, 13, to run on the I-beams, in the manner'indicated in Figs. 6. and 7.

Suspended from the underside of the turntable switch members I2, l2, as by welding thereto, are I-beams or supporting members l4, 14, having specially formed track-ways l4, M on opposite sides thereof on which run carrier wheels l5, l5, and l6, l6, as seen in Fig. 6. The

wheels 1'5, [5, are provided with yoke members 11, H, with a connecting member 18, supported at its opposite ends in said yoke members ll, ll. The wheels [6, 16, have the yoke members l9, IS, with a connecting member 20, supported at its opposite ends in said yoke members l9, 19. A supporting member 2|, is pivotally connected at its opposite ends with said connecting members l8 and 20, as indicated in Fig. .6, said supporting member 2| carrying the motor-operated hoisting mechanism, designated as a whole 22.

From said motor operated hoist mechanism, is suspended the motor-control cable '23, provided with electric buttons or switches, as 24 and 25, Figs. 6 and 3.

Suspended under the I-beam members l6, ID, as by welding, or otherwise, Figs. 5, 6 and '7, are I-beam track members 26, 26, with the trackways 26, 26', thereon, to receive the carrier wheels l5, l and [6, I6, said track members 26, 26, and their trackways 26', 26', being positioned to register with the corresponding track members I4, I4, and their trackways l4, l4, on the turntable switch structures, whereby said traveling hoist, load carrying mechanism, can be run from the stationary trackways on to the trackways of the turntable switch mechanism for the purpose of changing its direction, or course of travel, as may be desired. This general mechanism is not new, but is shown and described in order to explain how our invention is applied thereto.

Supported or suspended from the upper portions of the I-beam members l4 and 26, are insulating supporting members, as 21, 28, 29 and 30, each having at its lower end a clamp, as 3!,

for supporting trolley bars, designated 32, 33, 34 and 32', at intervals.

It will be noted that the insulating supporting member 21 is longer than are the other members 28, 29 and 30, the purpose for which will be explained later. These supporting members are shown in enlarged form in Figs. 8 and 9. The trolley bars 32, 33, 34 and 32', it will be noted, are supported along and above the trackways to receive the trolley wheels, or collectors, designated 35, 36 and 31, on the traveling hoist or load carrying mechanism, one pair of which 35, is seen in Fig. 6, in which said trolley wheels 35, 35, are shown mounted on the opposite ends of a rocking member 38, pivotally mounted in a switch box, 39, in which can be mounted the reversing switch mechanism, designated 42, in Figs. 3 and 4, in connection with the diagrammatic figure. This is shown in smaller compass in the switch box 39, Fig.6, to which is connected a cable or conduit for the wiring. This conduit is designated 40. The trolley wheels 35, 35, or collectors are mounted to swivel and to move up and down, as will be understood from Figs. 3, 4 and 6, so said trolley wheels can follow the trolle bars, whether low or high. 1

One of the important features of our invention is the mounting of one of the contact or trolley bars in a different position so that the current collectors or trolley wheels, as 35, 35, will be moved bodily relative to other wheels and in such a way as to cause the operation of an electric reversing switch. In the present showing, we have shown one of the trolley members 32 lower than the other three, as seen in Fig. 9, also in Figs. 3, 4 and 6.

In the diagrammatic view, Fig. 3, the trolley wheels 35, 35, being pivotally supported in the switch box 39, on the traveling hoist mechanism, are shown connected mechanically with a reversing switch mechanism, interposed in the circuit. This reversing switch mechanism is designated as a whole 42, and is designed to be operated by passing the trolley wheels along the differently positioned trolley bars or members.

This reversing switch mechanism may be described as follows: A lever 4| is pivotally mounted on a base 42, said lever having at its opposite ends two slots, 43, 43, with which are connected two plunger rods, 44 and 45, carrying at their lower ends contact or bridge bars 44' and 45', adapted to be moved into and out of engagement with four pairs of contact points, 46, 46; 41, 41';

and 48, 48'; and 49, 49, for opening and closing four different circuits, hereinafter referred to. This constitutes our auxiliary reversing switch, adapted to be actuated b the passing of the trolley or collector wheels, 35, 35, under the lower trolley bar or rail 32. In Fig. 4,'this auxiliary reversing switch is shown in the reversed position, having been moved to this position by a. coiled spring S on the plunger rod 44, when said trolley wheels 35, 35, moved on to a high or uniform trolley rail or bar, as 32',

In order to describe our invention and its operation, We refer particularly to Figs. 3 and 4, and also to Figs. 1 and 2. In Fig. 3, the hoist motor is designated M, and the up and down control switches are designated 24 and 25, respectively, and the auxiliary reversing switch is designated as a whole 42. Th regular motor control switch, a. magnetic switch, is designated R and its case is designated in broken heavy lines on Fig. 3.

Assuming that the traveling hoist 22, Fig. 6, is at the position X, on Fig. 1, with its trolley wheels 35, 35, in engagement with the lower trolley bar 32, with trolley wheel 36 in engagement with trolley bar 33, and with trolley wheel 3'! in engagement with trolley bar 34, Fig. 2, and also indicated in Fig. 9. No trolley wheel is in the position indicated in light broken lines at 35, Fig. 9. Our auxiliary switch 42 is in the position seen in Fig. 3. In this position the switch bar 44 is in engagement with contact points 49 and 49, and switch bar 45 is in engagement with contact points 46 and 46. They are in reversed positions in Fig. 4.

Assume now for explanatory purposes that the trolley bars 32 and 32 are fed with phase A, and conductor bar 33 is fed with phase B, and conductor bar 34 is fed with phase C, from the main line supply at all times, the operation may be described as follows:

If the up switch 24 be manually closed, a circuit, which we Will designate 65, is closed, and can be traced from the right hand side of said switch 24, through the limit switch 50, thence down to contacts 49', 49, thence up to solenoid 5!, of the regular magnetic motor control switch, thence up to juncture 65' and around and down to the supporting member 39, through trolley wheels 35, 35, to trolley bar or rail 32, and thence to phase A and to the main line. The energized solenoid 5i, closes the magnetic switch, in the right hand portion thereof, whereby the contacts 53, 53, 54, 54 and 55, 55 are closed, connecting the hoist motor M with the main line circuit, so that phase C connects by a circuit 0 with terminal 59 of said motor; phase A connects by a circuit a and circuit 65, with terminal 60 of said motor; and phase B connects by a circuit b with terminal 6| of said motor. The contacts in the left hand side of said magnetic switch are all open. The motor is operated to raise the load until it strikes and opens the limit switch 50, which automatically safeguards the hoist from damage. The releasing of the switch 24 will, of course, stop the hoist also.

Now if the down switch 25 is closed, a circuit therefrom, designated 66, will run to contacts 46, 46, of the reversing switch, thence up to solenoid 52, in the left hand portion of the magnetic switch, closing these switches at 56, 56; 51, 51', and 58, 58', and connecting the hoist motor M with the main line current, so that phase C connects by circuit 0, d and b with terminal 6| of the hoist motor; phase A connects by circuits 65, 66, e. and a with terminal 60 of said motor; and phase B connects by circuits b, J and c with terminal 59 of said motor, under which condition the hoist will lower the load until the manual switch is released. The circuit 66 continues from the solenoid 52 to the juncture with circuit 655, at 65', and thence through circuit 65 around to member 39, insulated from member 44, and thence to the trolley wheels 35, 35, trolley bar 32, and through phase A to the main line.

Assuming now that the hoist has moved from position X, Fig. 1, through switch H, up over the loop 12, down through switch 73, and back to switch 1 Switch H is first manually revolved through a forty-five degree angle clockwise, to the position indicated in Fig. 2, to allow the hoist to pass straight through to the starting position X. It will be realized now that the hoist has been turned completely around, and is facing in the opposite direction from its starting position.

There has been no change in the phase relationship between conductor bars or trolleys, and trolley wheels, until the hoist reaches switch H on the return trip. Up to this point, collector wheels 35, 35, have been in engagement with the low trolley bar 32, wheel 36 has been in engagement with trolley bar 33 and wheel 31 has been in engagement with trolley bar 34, with no trolley wheel on high bar 32,

As the hoist leaves turntable switch ll, Fig. 2, and returns to the position X, the phase relations are automatically changed and trolley wheels 35, 35, engage the high trolley bar 32, Fig. 4, trolley wheel 36 engages the high trolley bar 34, and trolley wheel 31 engages with high trolley bar 33. Since low trolley bar 32 and high trolley bar 32 are both connected with phase A, Fig. 4, there is no change in this phase through wheels 35, 35, to the hoist, but collector wheel 36 is now fed from phase C instead of phase B and collector wheel 31 is fed from phase B instead of phase C. This phase reversal would, under ordinary conditions, cause the hoist to operate in reverse and would operate to lower when the up switch is closed, and to raise when the down switch is closed, and as the up limit switch 50 is not in the down circuit, the hoist would be subject to damage, and the operator would be confused as to which switch to press, or operate.

Referring to Fig. 4, the collector trolley wheels 35, 35, have moved on to a high trolley bar, as 32'. Under the operation of the coiled spring S, on the plunger rod 44, the pivoted lever 41 has been moved to move the switch bridge bar 45' down to contacts 41, 41', and switch bridge bar 44' up to contacts 48, 48', closing the circuits, in reverse to the showing in Fig. 3. The other circuits, of course, are open.

In this position, if the up switch 24 is closed, the circuit including 65, the limit switch 50, contacts 41, 41', 66 and coil 52, closing magnetic wires e and a to hoist motor terminal 60.

switches 56, 56'; 51, 51 and 58, 58', and connecting the hoist motor M with the main circuit, is accomplished. Now the collector trolley wheels 35, 35, are connected with the high trolley bar 32' to phase A; wheel 36 is connected with high trolley bar 34, to phase C; and wheel 31 is connected with high trolley bar 33, to phase B, it will be seen that phase C will flow from trolley bar 34, through wheel 36 and through circuit wires b, I and through contacts 58, 58, and wire 0 to terminal 59, of the hoist motor M. Phase A will flow from trolley bar 32' through wheels 35, 35, through circuit wires 65, 66, points 51', 51 and B will flow from trolley bar 33, through wheel 31, through wires 0 and d and through contact points 56, 56, and wire b, to hoist motor terminal 6|. Under this phasing, the hoist will raise the load, and the up limit switch and the up switch 24 will function properly.

It should also be clear that the down switch 25 will function properly, and there will be no wrong or reverse action from what is intended when the up or the down switches are actuated to move the load up or down.

Thus we have interposed a reversing switch in the control circuits for a traveling hoist, with mechanical means connected with the traveling hoist mechanism for actuating said reversing switch when said traveling hoist has been reversed in its travel, whereby to automatically reverse the circuit in keeping with the reversal of the position of the traveling hoist relative to the trackways on which it moves.

We do not limit our invention to the details of the showing here made for the purposes of illustrating one embodiment of our invention, except as we may be limited by the hereto appended claim.

We claim:

In a traveling hoist system using a three phase alternating current, a reversible motor, tracks, and a control switch for starting and stopping said motor in each direction of rotation, an auxiliary control switch adapted to reverse the connections to said control switches, said auxiliary control switch having means for mechanically operating the same, said means being automatically operable by the reversal of the hoist on the track in its course of travel, and a plurality of trolley bars associated with said tracks for supplying current to said motor and for actuating said means for operating said auxiliary control switch during the movement of said hoist on said tracks, one of said trolley bars being placed at a different elevation to the other trolley bars for this purpose said trolley bars being symmetrically located transversely with respect to said tracks.

ARTHUR L. MEDENWALD. EARL B. SPENCER.

Phase 

